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                        <h1 id="%E5%8F%98%E9%87%8F%E7%9A%84%E8%A7%A3%E6%9E%84%E8%B5%8B%E5%80%BC">&#x53D8;&#x91CF;&#x7684;&#x89E3;&#x6784;&#x8D4B;&#x503C;</h1>
<h2 id="%E6%95%B0%E7%BB%84%E7%9A%84%E8%A7%A3%E6%9E%84%E8%B5%8B%E5%80%BC">&#x6570;&#x7EC4;&#x7684;&#x89E3;&#x6784;&#x8D4B;&#x503C;</h2>
<p>ES6&#x5141;&#x8BB8;&#x6309;&#x7167;&#x4E00;&#x5B9A;&#x6A21;&#x5F0F;&#xFF0C;&#x4ECE;&#x6570;&#x7EC4;&#x548C;&#x5BF9;&#x8C61;&#x4E2D;&#x63D0;&#x53D6;&#x503C;&#xFF0C;&#x5BF9;&#x53D8;&#x91CF;&#x8FDB;&#x884C;&#x8D4B;&#x503C;&#xFF0C;&#x8FD9;&#x88AB;&#x79F0;&#x4E3A;&#x89E3;&#x6784;&#xFF08;Destructuring&#xFF09;&#x3002;</p>
<p>&#x4EE5;&#x524D;&#xFF0C;&#x4E3A;&#x53D8;&#x91CF;&#x8D4B;&#x503C;&#xFF0C;&#x53EA;&#x80FD;&#x76F4;&#x63A5;&#x6307;&#x5B9A;&#x503C;&#x3002;</p>
<pre><code class="lang-javascript">
<span class="hljs-keyword">var</span> a = <span class="hljs-number">1</span>;
<span class="hljs-keyword">var</span> b = <span class="hljs-number">2</span>;
<span class="hljs-keyword">var</span> c = <span class="hljs-number">3</span>;
</code></pre>
<p>ES6&#x5141;&#x8BB8;&#x5199;&#x6210;&#x4E0B;&#x9762;&#x8FD9;&#x6837;&#x3002;</p>
<pre><code class="lang-javascript">
<span class="hljs-keyword">var</span> [a, b, c] = [<span class="hljs-number">1</span>, <span class="hljs-number">2</span>, <span class="hljs-number">3</span>];
</code></pre>
<p>&#x4E0A;&#x9762;&#x4EE3;&#x7801;&#x8868;&#x793A;&#xFF0C;&#x53EF;&#x4EE5;&#x4ECE;&#x6570;&#x7EC4;&#x4E2D;&#x63D0;&#x53D6;&#x503C;&#xFF0C;&#x6309;&#x7167;&#x5BF9;&#x5E94;&#x4F4D;&#x7F6E;&#xFF0C;&#x5BF9;&#x53D8;&#x91CF;&#x8D4B;&#x503C;&#x3002;</p>
<p>&#x672C;&#x8D28;&#x4E0A;&#xFF0C;&#x8FD9;&#x79CD;&#x5199;&#x6CD5;&#x5C5E;&#x4E8E;&#x201C;&#x6A21;&#x5F0F;&#x5339;&#x914D;&#x201D;&#xFF0C;&#x53EA;&#x8981;&#x7B49;&#x53F7;&#x4E24;&#x8FB9;&#x7684;&#x6A21;&#x5F0F;&#x76F8;&#x540C;&#xFF0C;&#x5DE6;&#x8FB9;&#x7684;&#x53D8;&#x91CF;&#x5C31;&#x4F1A;&#x88AB;&#x8D4B;&#x4E88;&#x5BF9;&#x5E94;&#x7684;&#x503C;&#x3002;&#x4E0B;&#x9762;&#x662F;&#x4E00;&#x4E9B;&#x4F7F;&#x7528;&#x5D4C;&#x5957;&#x6570;&#x7EC4;&#x8FDB;&#x884C;&#x89E3;&#x6784;&#x7684;&#x4F8B;&#x5B50;&#x3002;</p>
<pre><code class="lang-javascript">
<span class="hljs-keyword">var</span> [foo, [[bar], baz]] = [<span class="hljs-number">1</span>, [[<span class="hljs-number">2</span>], <span class="hljs-number">3</span>]];
foo <span class="hljs-comment">// 1</span>
bar <span class="hljs-comment">// 2</span>
baz <span class="hljs-comment">// 3</span>

<span class="hljs-keyword">var</span> [,,third] = [<span class="hljs-string">&quot;foo&quot;</span>, <span class="hljs-string">&quot;bar&quot;</span>, <span class="hljs-string">&quot;baz&quot;</span>];
third <span class="hljs-comment">// &quot;baz&quot;</span>

<span class="hljs-keyword">var</span> [head, ...tail] = [<span class="hljs-number">1</span>, <span class="hljs-number">2</span>, <span class="hljs-number">3</span>, <span class="hljs-number">4</span>];
head <span class="hljs-comment">// 1</span>
tail <span class="hljs-comment">// [2, 3, 4]</span>
</code></pre>
<p>&#x5982;&#x679C;&#x89E3;&#x6784;&#x4E0D;&#x6210;&#x529F;&#xFF0C;&#x53D8;&#x91CF;&#x7684;&#x503C;&#x5C31;&#x7B49;&#x4E8E;undefined&#x3002;</p>
<pre><code class="lang-javascript">
<span class="hljs-keyword">var</span> [foo] = [];
<span class="hljs-keyword">var</span> [foo] = <span class="hljs-number">1</span>;
<span class="hljs-keyword">var</span> [foo] = <span class="hljs-string">&apos;Hello&apos;</span>;
<span class="hljs-keyword">var</span> [foo] = <span class="hljs-literal">false</span>;
<span class="hljs-keyword">var</span> [foo] = <span class="hljs-literal">NaN</span>;
<span class="hljs-keyword">var</span> [bar, foo] = [<span class="hljs-number">1</span>];
</code></pre>
<p>&#x4EE5;&#x4E0A;&#x51E0;&#x79CD;&#x60C5;&#x51B5;&#x90FD;&#x5C5E;&#x4E8E;&#x89E3;&#x6784;&#x4E0D;&#x6210;&#x529F;&#xFF0C;foo&#x7684;&#x503C;&#x90FD;&#x4F1A;&#x7B49;&#x4E8E;undefined&#x3002;&#x53E6;&#x4E00;&#x79CD;&#x60C5;&#x51B5;&#x662F;&#x4E0D;&#x5B8C;&#x5168;&#x89E3;&#x6784;&#x3002;</p>
<pre><code class="lang-javascript">
<span class="hljs-keyword">var</span> [x, y] = [<span class="hljs-number">1</span>, <span class="hljs-number">2</span>, <span class="hljs-number">3</span>];
</code></pre>
<p>&#x4E0A;&#x9762;&#x4EE3;&#x7801;&#x4E2D;&#xFF0C;x&#x548C;y&#x53EF;&#x4EE5;&#x987A;&#x5229;&#x53D6;&#x5230;&#x503C;&#x3002;</p>
<p>&#x5982;&#x679C;&#x5BF9;undefined&#x6216;null&#x8FDB;&#x884C;&#x89E3;&#x6784;&#xFF0C;&#x4F1A;&#x62A5;&#x9519;&#x3002;</p>
<pre><code class="lang-javascript">
<span class="hljs-comment">// &#x62A5;&#x9519;</span>
<span class="hljs-keyword">var</span> [foo] = <span class="hljs-literal">undefined</span>;
<span class="hljs-keyword">var</span> [foo] = <span class="hljs-literal">null</span>;
</code></pre>
<p>&#x8FD9;&#x662F;&#x56E0;&#x4E3A;&#x89E3;&#x6784;&#x53EA;&#x80FD;&#x7528;&#x4E8E;&#x6570;&#x7EC4;&#x6216;&#x5BF9;&#x8C61;&#x3002;&#x5176;&#x4ED6;&#x539F;&#x59CB;&#x7C7B;&#x578B;&#x7684;&#x503C;&#x90FD;&#x53EF;&#x4EE5;&#x8F6C;&#x4E3A;&#x76F8;&#x5E94;&#x7684;&#x5BF9;&#x8C61;&#xFF0C;&#x4F46;&#x662F;&#xFF0C;undefined&#x548C;null&#x4E0D;&#x80FD;&#x8F6C;&#x4E3A;&#x5BF9;&#x8C61;&#xFF0C;&#x56E0;&#x6B64;&#x62A5;&#x9519;&#x3002;</p>
<p>&#x89E3;&#x6784;&#x8D4B;&#x503C;&#x5141;&#x8BB8;&#x6307;&#x5B9A;&#x9ED8;&#x8BA4;&#x503C;&#x3002;</p>
<pre><code class="lang-javascript">
<span class="hljs-keyword">var</span> [foo = <span class="hljs-literal">true</span>] = [];
foo <span class="hljs-comment">// true</span>

[x, y=<span class="hljs-string">&apos;b&apos;</span>] = [<span class="hljs-string">&apos;a&apos;</span>] <span class="hljs-comment">// x=&apos;a&apos;, y=&apos;b&apos;</span>
[x, y=<span class="hljs-string">&apos;b&apos;</span>] = [<span class="hljs-string">&apos;a&apos;</span>, <span class="hljs-literal">undefined</span>] <span class="hljs-comment">// x=&apos;a&apos;, y=&apos;b&apos;</span>
</code></pre>
<p>&#x89E3;&#x6784;&#x8D4B;&#x503C;&#x4E0D;&#x4EC5;&#x9002;&#x7528;&#x4E8E;var&#x547D;&#x4EE4;&#xFF0C;&#x4E5F;&#x9002;&#x7528;&#x4E8E;let&#x548C;const&#x547D;&#x4EE4;&#x3002;</p>
<pre><code class="lang-javascript">
<span class="hljs-keyword">var</span> [v1, v2, ..., vN ] = array;
<span class="hljs-keyword">let</span> [v1, v2, ..., vN ] = array;
<span class="hljs-keyword">const</span> [v1, v2, ..., vN ] = array;
</code></pre>
<p>&#x5BF9;&#x4E8E;Set&#x7ED3;&#x6784;&#xFF0C;&#x4E5F;&#x53EF;&#x4EE5;&#x4F7F;&#x7528;&#x6570;&#x7EC4;&#x7684;&#x89E3;&#x6784;&#x8D4B;&#x503C;&#x3002;</p>
<pre><code class="lang-javascript">
[a, b, c] = <span class="hljs-keyword">new</span> <span class="hljs-built_in">Set</span>([<span class="hljs-string">&quot;a&quot;</span>, <span class="hljs-string">&quot;b&quot;</span>, <span class="hljs-string">&quot;c&quot;</span>])
a <span class="hljs-comment">// &quot;a&quot;</span>
</code></pre>
<p>&#x4E8B;&#x5B9E;&#x4E0A;&#xFF0C;&#x53EA;&#x8981;&#x67D0;&#x79CD;&#x6570;&#x636E;&#x7ED3;&#x6784;&#x5177;&#x6709;Iterator&#x63A5;&#x53E3;&#xFF0C;&#x90FD;&#x53EF;&#x4EE5;&#x91C7;&#x7528;&#x6570;&#x7EC4;&#x5F62;&#x5F0F;&#x7684;&#x7ED3;&#x6784;&#x8D4B;&#x503C;&#x3002;</p>
<h2 id="%E5%AF%B9%E8%B1%A1%E7%9A%84%E8%A7%A3%E6%9E%84%E8%B5%8B%E5%80%BC">&#x5BF9;&#x8C61;&#x7684;&#x89E3;&#x6784;&#x8D4B;&#x503C;</h2>
<p>&#x89E3;&#x6784;&#x4E0D;&#x4EC5;&#x53EF;&#x4EE5;&#x7528;&#x4E8E;&#x6570;&#x7EC4;&#xFF0C;&#x8FD8;&#x53EF;&#x4EE5;&#x7528;&#x4E8E;&#x5BF9;&#x8C61;&#x3002;</p>
<pre><code class="lang-javascript">
<span class="hljs-keyword">var</span> { foo, bar } = { foo: <span class="hljs-string">&quot;aaa&quot;</span>, bar: <span class="hljs-string">&quot;bbb&quot;</span> };
foo <span class="hljs-comment">// &quot;aaa&quot;</span>
bar <span class="hljs-comment">// &quot;bbb&quot;</span>
</code></pre>
<p>&#x5BF9;&#x8C61;&#x7684;&#x89E3;&#x6784;&#x4E0E;&#x6570;&#x7EC4;&#x6709;&#x4E00;&#x4E2A;&#x91CD;&#x8981;&#x7684;&#x4E0D;&#x540C;&#x3002;&#x6570;&#x7EC4;&#x7684;&#x5143;&#x7D20;&#x662F;&#x6309;&#x6B21;&#x5E8F;&#x6392;&#x5217;&#x7684;&#xFF0C;&#x53D8;&#x91CF;&#x7684;&#x53D6;&#x503C;&#x7531;&#x5B83;&#x7684;&#x4F4D;&#x7F6E;&#x51B3;&#x5B9A;&#xFF1B;&#x800C;&#x5BF9;&#x8C61;&#x7684;&#x5C5E;&#x6027;&#x6CA1;&#x6709;&#x6B21;&#x5E8F;&#xFF0C;&#x53D8;&#x91CF;&#x5FC5;&#x987B;&#x4E0E;&#x5C5E;&#x6027;&#x540C;&#x540D;&#xFF0C;&#x624D;&#x80FD;&#x53D6;&#x5230;&#x6B63;&#x786E;&#x7684;&#x503C;&#x3002;</p>
<pre><code class="lang-javascript">
<span class="hljs-keyword">var</span> { bar, foo } = { foo: <span class="hljs-string">&quot;aaa&quot;</span>, bar: <span class="hljs-string">&quot;bbb&quot;</span> };
foo <span class="hljs-comment">// &quot;aaa&quot;</span>
bar <span class="hljs-comment">// &quot;bbb&quot;</span>

<span class="hljs-keyword">var</span> { baz } = { foo: <span class="hljs-string">&quot;aaa&quot;</span>, bar: <span class="hljs-string">&quot;bbb&quot;</span> };
baz <span class="hljs-comment">// undefined</span>
</code></pre>
<p>&#x4E0A;&#x9762;&#x4EE3;&#x7801;&#x7684;&#x7B2C;&#x4E00;&#x4E2A;&#x4F8B;&#x5B50;&#xFF0C;&#x7B49;&#x53F7;&#x5DE6;&#x8FB9;&#x7684;&#x4E24;&#x4E2A;&#x53D8;&#x91CF;&#x7684;&#x6B21;&#x5E8F;&#xFF0C;&#x4E0E;&#x7B49;&#x53F7;&#x53F3;&#x8FB9;&#x4E24;&#x4E2A;&#x540C;&#x540D;&#x5C5E;&#x6027;&#x7684;&#x6B21;&#x5E8F;&#x4E0D;&#x4E00;&#x81F4;&#xFF0C;&#x4F46;&#x662F;&#x5BF9;&#x53D6;&#x503C;&#x5B8C;&#x5168;&#x6CA1;&#x6709;&#x5F71;&#x54CD;&#x3002;&#x7B2C;&#x4E8C;&#x4E2A;&#x4F8B;&#x5B50;&#x7684;&#x53D8;&#x91CF;&#x6CA1;&#x6709;&#x5BF9;&#x5E94;&#x7684;&#x540C;&#x540D;&#x5C5E;&#x6027;&#xFF0C;&#x5BFC;&#x81F4;&#x53D6;&#x4E0D;&#x5230;&#x503C;&#xFF0C;&#x6700;&#x540E;&#x7B49;&#x4E8E;<code>undefined</code>&#x3002;</p>
<p>&#x5982;&#x679C;&#x53D8;&#x91CF;&#x540D;&#x4E0E;&#x5C5E;&#x6027;&#x540D;&#x4E0D;&#x4E00;&#x81F4;&#xFF0C;&#x5FC5;&#x987B;&#x5199;&#x6210;&#x4E0B;&#x9762;&#x8FD9;&#x6837;&#x3002;</p>
<pre><code class="lang-javascript">
<span class="hljs-keyword">var</span> { foo: baz } = { foo: <span class="hljs-string">&quot;aaa&quot;</span>, bar: <span class="hljs-string">&quot;bbb&quot;</span> };
baz <span class="hljs-comment">// &quot;aaa&quot;</span>
</code></pre>
<p>&#x548C;&#x6570;&#x7EC4;&#x4E00;&#x6837;&#xFF0C;&#x89E3;&#x6784;&#x4E5F;&#x53EF;&#x4EE5;&#x7528;&#x4E8E;&#x5D4C;&#x5957;&#x7ED3;&#x6784;&#x7684;&#x5BF9;&#x8C61;&#x3002;</p>
<pre><code class="lang-javascript">
<span class="hljs-keyword">var</span> o = {
  p: [
    <span class="hljs-string">&quot;Hello&quot;</span>,
    { y: <span class="hljs-string">&quot;World&quot;</span> }
  ]
};

<span class="hljs-keyword">var</span> { p: [x, { y }] } = o;
x <span class="hljs-comment">// &quot;Hello&quot;</span>
y <span class="hljs-comment">// &quot;World&quot;</span>
</code></pre>
<p>&#x5BF9;&#x8C61;&#x7684;&#x89E3;&#x6784;&#x4E5F;&#x53EF;&#x4EE5;&#x6307;&#x5B9A;&#x9ED8;&#x8BA4;&#x503C;&#x3002;</p>
<pre><code class="lang-javascript">
<span class="hljs-keyword">var</span> { x = <span class="hljs-number">3</span> } = {};
x <span class="hljs-comment">// 3</span>

<span class="hljs-keyword">var</span> {x, y = <span class="hljs-number">5</span>} = {x: <span class="hljs-number">1</span>};
<span class="hljs-built_in">console</span>.log(x, y) <span class="hljs-comment">// 1, 5</span>
</code></pre>
<p>&#x5982;&#x679C;&#x8981;&#x5C06;&#x4E00;&#x4E2A;&#x5DF2;&#x7ECF;&#x58F0;&#x660E;&#x7684;&#x53D8;&#x91CF;&#x7528;&#x4E8E;&#x89E3;&#x6784;&#x8D4B;&#x503C;&#xFF0C;&#x5FC5;&#x987B;&#x975E;&#x5E38;&#x5C0F;&#x5FC3;&#x3002;</p>
<pre><code class="lang-javascript">
<span class="hljs-comment">// &#x9519;&#x8BEF;&#x7684;&#x5199;&#x6CD5;</span>

<span class="hljs-keyword">var</span> x;
{x} = {x:<span class="hljs-number">1</span>};
<span class="hljs-comment">// SyntaxError: syntax error</span>
</code></pre>
<p>&#x4E0A;&#x9762;&#x4EE3;&#x7801;&#x7684;&#x5199;&#x6CD5;&#x4F1A;&#x62A5;&#x9519;&#xFF0C;&#x56E0;&#x4E3A;JavaScript&#x5F15;&#x64CE;&#x4F1A;&#x5C06;<code>{x}</code>&#x7406;&#x89E3;&#x6210;&#x4E00;&#x4E2A;&#x4EE3;&#x7801;&#x5757;&#xFF0C;&#x4ECE;&#x800C;&#x53D1;&#x751F;&#x8BED;&#x6CD5;&#x9519;&#x8BEF;&#x3002;&#x53EA;&#x6709;&#x4E0D;&#x5C06;&#x5927;&#x62EC;&#x53F7;&#x5199;&#x5728;&#x884C;&#x9996;&#xFF0C;&#x907F;&#x514D;JavaScript&#x5C06;&#x5176;&#x89E3;&#x91CA;&#x4E3A;&#x4EE3;&#x7801;&#x5757;&#xFF0C;&#x624D;&#x80FD;&#x89E3;&#x51B3;&#x8FD9;&#x4E2A;&#x95EE;&#x9898;&#x3002;</p>
<pre><code class="lang-javascript">
<span class="hljs-comment">// &#x6B63;&#x786E;&#x7684;&#x5199;&#x6CD5;</span>

({x}) = {x:<span class="hljs-number">1</span>};
<span class="hljs-comment">// &#x6216;&#x8005;</span>
({x} = {x:<span class="hljs-number">1</span>});
</code></pre>
<h2 id="%E7%94%A8%E9%80%94">&#x7528;&#x9014;</h2>
<p>&#x53D8;&#x91CF;&#x7684;&#x89E3;&#x6784;&#x8D4B;&#x503C;&#x7528;&#x9014;&#x5F88;&#x591A;&#x3002;</p>
<p><strong>&#xFF08;1&#xFF09;&#x4EA4;&#x6362;&#x53D8;&#x91CF;&#x7684;&#x503C;</strong></p>
<pre><code class="lang-javascript">
[x, y] = [y, x];
</code></pre>
<p><strong>&#xFF08;2&#xFF09;&#x4ECE;&#x51FD;&#x6570;&#x8FD4;&#x56DE;&#x591A;&#x4E2A;&#x503C;</strong></p>
<p>&#x51FD;&#x6570;&#x53EA;&#x80FD;&#x8FD4;&#x56DE;&#x4E00;&#x4E2A;&#x503C;&#xFF0C;&#x5982;&#x679C;&#x8981;&#x8FD4;&#x56DE;&#x591A;&#x4E2A;&#x503C;&#xFF0C;&#x53EA;&#x80FD;&#x5C06;&#x5B83;&#x4EEC;&#x653E;&#x5728;&#x6570;&#x7EC4;&#x6216;&#x5BF9;&#x8C61;&#x91CC;&#x8FD4;&#x56DE;&#x3002;&#x6709;&#x4E86;&#x89E3;&#x6784;&#x8D4B;&#x503C;&#xFF0C;&#x53D6;&#x51FA;&#x8FD9;&#x4E9B;&#x503C;&#x5C31;&#x975E;&#x5E38;&#x65B9;&#x4FBF;&#x3002;</p>
<pre><code class="lang-javascript">
<span class="hljs-comment">// &#x8FD4;&#x56DE;&#x4E00;&#x4E2A;&#x6570;&#x7EC4;</span>

<span class="hljs-function"><span class="hljs-keyword">function</span> <span class="hljs-title">example</span>(<span class="hljs-params"></span>) </span>{
    <span class="hljs-keyword">return</span> [<span class="hljs-number">1</span>, <span class="hljs-number">2</span>, <span class="hljs-number">3</span>];
}
<span class="hljs-keyword">var</span> [a, b, c] = example();

<span class="hljs-comment">// &#x8FD4;&#x56DE;&#x4E00;&#x4E2A;&#x5BF9;&#x8C61;</span>

<span class="hljs-function"><span class="hljs-keyword">function</span> <span class="hljs-title">example</span>(<span class="hljs-params"></span>) </span>{
  <span class="hljs-keyword">return</span> {
    foo: <span class="hljs-number">1</span>,
    bar: <span class="hljs-number">2</span>
  };
}
<span class="hljs-keyword">var</span> { foo, bar } = example();
</code></pre>
<p><strong>&#xFF08;3&#xFF09;&#x51FD;&#x6570;&#x53C2;&#x6570;&#x7684;&#x5B9A;&#x4E49;</strong></p>
<pre><code class="lang-javascript">
<span class="hljs-function"><span class="hljs-keyword">function</span> <span class="hljs-title">f</span>(<span class="hljs-params">[x]</span>) </span>{ ... }

f([<span class="hljs-string">&apos;a&apos;</span>])

<span class="hljs-function"><span class="hljs-keyword">function</span> <span class="hljs-title">f</span>(<span class="hljs-params">{x, y, z}</span>) </span>{ ... }

f({x:<span class="hljs-number">1</span>, y:<span class="hljs-number">2</span>, z:<span class="hljs-number">3</span>})
</code></pre>
<p>&#x8FD9;&#x79CD;&#x5199;&#x6CD5;&#x5BF9;&#x63D0;&#x53D6;JSON&#x5BF9;&#x8C61;&#x4E2D;&#x7684;&#x6570;&#x636E;&#xFF0C;&#x5C24;&#x5176;&#x6709;&#x7528;&#x3002;</p>
<p><strong>&#xFF08;4&#xFF09;&#x51FD;&#x6570;&#x53C2;&#x6570;&#x7684;&#x9ED8;&#x8BA4;&#x503C;</strong></p>
<pre><code class="lang-javascript">
jQuery.ajax = <span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">url, {
  async = true,
  beforeSend = function (</span>) </span>{},
  cache = <span class="hljs-literal">true</span>,
  complete = <span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params"></span>) </span>{},
  crossDomain = <span class="hljs-literal">false</span>,
  global = <span class="hljs-literal">true</span>,
  <span class="hljs-comment">// ... more config</span>
}) {
  <span class="hljs-comment">// ... do stuff</span>
};
</code></pre>
<p>&#x6307;&#x5B9A;&#x53C2;&#x6570;&#x7684;&#x9ED8;&#x8BA4;&#x503C;&#xFF0C;&#x5C31;&#x907F;&#x514D;&#x4E86;&#x5728;&#x51FD;&#x6570;&#x4F53;&#x5185;&#x90E8;&#x518D;&#x5199;<code>var foo = config.foo || &apos;default foo&apos;;</code>&#x8FD9;&#x6837;&#x7684;&#x8BED;&#x53E5;&#x3002;</p>
<p><strong>&#xFF08;5&#xFF09;&#x904D;&#x5386;Map&#x7ED3;&#x6784;</strong></p>
<p>&#x4EFB;&#x4F55;&#x90E8;&#x7F72;&#x4E86;Iterator&#x63A5;&#x53E3;&#x7684;&#x5BF9;&#x8C61;&#xFF0C;&#x90FD;&#x53EF;&#x4EE5;&#x7528;for...of&#x5FAA;&#x73AF;&#x904D;&#x5386;&#x3002;Map&#x7ED3;&#x6784;&#x539F;&#x751F;&#x652F;&#x6301;Iterator&#x63A5;&#x53E3;&#xFF0C;&#x914D;&#x5408;&#x53D8;&#x91CF;&#x7684;&#x7ED3;&#x6784;&#x8D4B;&#x503C;&#xFF0C;&#x83B7;&#x53D6;&#x952E;&#x540D;&#x548C;&#x952E;&#x503C;&#x5C31;&#x975E;&#x5E38;&#x65B9;&#x4FBF;&#x3002;</p>
<pre><code class="lang-javascript">
<span class="hljs-keyword">var</span> map = <span class="hljs-keyword">new</span> <span class="hljs-built_in">Map</span>();
map.set(<span class="hljs-string">&apos;first&apos;</span>, <span class="hljs-string">&apos;hello&apos;</span>);
map.set(<span class="hljs-string">&apos;second&apos;</span>, <span class="hljs-string">&apos;world&apos;</span>);

<span class="hljs-keyword">for</span> (<span class="hljs-keyword">let</span> [key, value] <span class="hljs-keyword">of</span> map) {
  <span class="hljs-built_in">console</span>.log(key + <span class="hljs-string">&quot; is &quot;</span> + value);
}
<span class="hljs-comment">// first is hello</span>
<span class="hljs-comment">// second is world</span>
</code></pre>
<p>&#x5982;&#x679C;&#x53EA;&#x60F3;&#x83B7;&#x53D6;&#x952E;&#x540D;&#xFF0C;&#x6216;&#x8005;&#x53EA;&#x60F3;&#x83B7;&#x53D6;&#x952E;&#x503C;&#xFF0C;&#x53EF;&#x4EE5;&#x5199;&#x6210;&#x4E0B;&#x9762;&#x8FD9;&#x6837;&#x3002;</p>
<pre><code class="lang-javascript">
<span class="hljs-comment">// &#x83B7;&#x53D6;&#x952E;&#x540D;</span>
<span class="hljs-keyword">for</span> (<span class="hljs-keyword">let</span> [key] <span class="hljs-keyword">of</span> map) {
  <span class="hljs-comment">// ...</span>
}

<span class="hljs-comment">// &#x83B7;&#x53D6;&#x952E;&#x503C;</span>
<span class="hljs-keyword">for</span> (<span class="hljs-keyword">let</span> [,value] <span class="hljs-keyword">of</span> map) {
  <span class="hljs-comment">// ...</span>
}
</code></pre>
<p><strong>&#xFF08;6&#xFF09;&#x8F93;&#x5165;&#x6A21;&#x5757;&#x7684;&#x6307;&#x5B9A;&#x65B9;&#x6CD5;</strong></p>
<p>&#x52A0;&#x8F7D;&#x6A21;&#x5757;&#x65F6;&#xFF0C;&#x5F80;&#x5F80;&#x9700;&#x8981;&#x6307;&#x5B9A;&#x8F93;&#x5165;&#x90A3;&#x4E9B;&#x65B9;&#x6CD5;&#x3002;&#x89E3;&#x6784;&#x8D4B;&#x503C;&#x4F7F;&#x5F97;&#x8F93;&#x5165;&#x8BED;&#x53E5;&#x975E;&#x5E38;&#x6E05;&#x6670;&#x3002;</p>
<pre><code class="lang-javascript">
<span class="hljs-keyword">const</span> { SourceMapConsumer, SourceNode } = <span class="hljs-built_in">require</span>(<span class="hljs-string">&quot;source-map&quot;</span>);
</code></pre>

                    
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